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cpointerslvalue

Incrementing pointer in function argument

I have the following code:

int x;
int * xPtr = &x;

int * Get_xPtr(void);
void someFunction(int * y);

int * Get_xPtr(void)
{
    return xPtr;
}

void someFunction(int * y)
{
    ...
    ...
}

void main(void)
{
    someFunction(++Get_xPtr());
}

This code is compiling fine without the increment on the return value (address) of function Get_xPtr(), but with the increment I get the error:

"error: lvalue required as increment operand"

I guess this is not allowed syntax, but why? Is there any other way to do this or do I need to:

int * tempPtr = GetxPtr();
tempPtr++;
someFunction(tempPtr);
Solution 
  • someFunction(++Get_xPtr());

    ++Get_xptr() requires lvalue to store return value.

    simple example will make some clarification

    int i=0;
++i; ==>i=i+1; //result stored in i.

    variable i can change 

    ++5; //where is lvalue ?

    You can use 

    someFunction(Get_xPtr()+1);